#usda 1.0 ( "WARNING: THIS FILE IS GENERATED BY usdGenSchema. DO NOT EDIT." ) class "LightAPI" ( apiSchemas = ["CollectionAPI:lightLink", "CollectionAPI:shadowLink"] customData = { token[] apiSchemaOverridePropertyNames = ["collection:lightLink:includeRoot", "collection:shadowLink:includeRoot"] } doc = """API schema that imparts the quality of being a light onto a prim. A light is any prim that has this schema applied to it. This is true regardless of whether LightAPI is included as a built-in API of the prim type (e.g. RectLight or DistantLight) or is applied directly to a Gprim that should be treated as a light. Linking Lights can be linked to geometry. Linking controls which geometry a light illuminates, and which geometry casts shadows from the light. Linking is specified as collections (UsdCollectionAPI) which can be accessed via GetLightLinkCollection() and GetShadowLinkCollection(). Note that these collections have their includeRoot set to true, so that lights will illuminate and cast shadows from all objects by default. To illuminate only a specific set of objects, there are two options. One option is to modify the collection paths to explicitly exclude everything else, assuming it is known; the other option is to set includeRoot to false and explicitly include the desired objects. These are complementary approaches that may each be preferable depending on the scenario and how to best express the intent of the light setup. """ ) { uniform bool collection:lightLink:includeRoot = 1 uniform bool collection:shadowLink:includeRoot = 1 color3f inputs:color = (1, 1, 1) ( displayGroup = "Basic" displayName = "Color" doc = "The color of emitted light, in energy-linear terms." ) float inputs:colorTemperature = 6500 ( displayGroup = "Basic" displayName = "Color Temperature" doc = """Color temperature, in degrees Kelvin, representing the white point. The default is a common white point, D65. Lower values are warmer and higher values are cooler. The valid range is from 1000 to 10000. Only takes effect when enableColorTemperature is set to true. When active, the computed result multiplies against the color attribute. See UsdLuxBlackbodyTemperatureAsRgb().""" ) float inputs:diffuse = 1 ( displayGroup = "Refine" displayName = "Diffuse Multiplier" doc = """A multiplier for the effect of this light on the diffuse response of materials. This is a non-physical control.""" ) bool inputs:enableColorTemperature = 0 ( displayGroup = "Basic" displayName = "Enable Color Temperature" doc = "Enables using colorTemperature." ) float inputs:exposure = 0 ( displayGroup = "Basic" displayName = "Exposure" doc = """Scales the power of the light exponentially as a power of 2 (similar to an F-stop control over exposure). The result is multiplied against the intensity.""" ) float inputs:intensity = 1 ( displayGroup = "Basic" displayName = "Intensity" doc = "Scales the power of the light linearly." ) bool inputs:normalize = 0 ( displayGroup = "Advanced" displayName = "Normalize Power" doc = """Normalizes power by the surface area of the light. This makes it easier to independently adjust the power and shape of the light, by causing the power to not vary with the area or angular size of the light.""" ) float inputs:specular = 1 ( displayGroup = "Refine" displayName = "Specular Multiplier" doc = """A multiplier for the effect of this light on the specular response of materials. This is a non-physical control.""" ) rel light:filters ( doc = "Relationship to the light filters that apply to this light." ) uniform token light:materialSyncMode = "noMaterialResponse" ( allowedTokens = ["materialGlowTintsLight", "independent", "noMaterialResponse"] displayGroup = "Geometry" displayName = "Material Sync Mode" doc = """For a LightAPI applied to geometry that has a bound Material, which is entirely or partly emissive, this specifies the relationship of the Material response to the lighting response. Valid values are: - materialGlowTintsLight: All primary and secondary rays see the emissive/glow response as dictated by the bound Material while the base color seen by light rays (which is then modulated by all of the other LightAPI controls) is the multiplication of the color feeding the emission/glow input of the Material (i.e. its surface or volume shader) with the scalar or pattern input to *inputs:color*. This allows the light's color to tint the geometry's glow color while preserving access to intensity and other light controls as ways to further modulate the illumination. - independent: All primary and secondary rays see the emissive/glow response as dictated by the bound Material, while the base color seen by light rays is determined solely by *inputs:color*. Note that for partially emissive geometry (in which some parts are reflective rather than emissive), a suitable pattern must be connected to the light's color input, or else the light will radiate uniformly from the geometry. - noMaterialResponse: The geometry behaves as if there is no Material bound at all, i.e. there is no diffuse, specular, or transmissive response. The base color of light rays is entirely controlled by the *inputs:color*. This is the standard mode for \"canonical\" lights in UsdLux and indicates to renderers that a Material will either never be bound or can always be ignored. """ ) uniform token light:shaderId = "" ( displayGroup = "Internal" doc = """Default ID for the light's shader. This defines the shader ID for this light when a render context specific shader ID is not available. The default shaderId for the intrinsic UsdLux lights (RectLight, DistantLight, etc.) are set to default to the light's type name. For each intrinsic UsdLux light, we will always register an SdrShaderNode in the SdrRegistry, with the identifier matching the type name and the source type \"USD\", that corresponds to the light's inputs. \\see GetShaderId \\see GetShaderIdAttrForRenderContext \\see SdrRegistry::GetShaderNodeByIdentifier \\see SdrRegistry::GetShaderNodeByIdentifierAndType """ ) } class "MeshLightAPI" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:materialSyncMode", "light:shaderId"] } doc = '''This is the preferred API schema to apply to "Mesh" type prims when adding light behaviors to a mesh. At its base, this API schema has the built-in behavior of applying LightAPI to the mesh and overriding the default materialSyncMode to allow the emission/glow of the bound material to affect the color of the light. But, it additionally serves as a hook for plugins to attach additional properties to "mesh lights" through the creation of API schemas which are authored to auto-apply to MeshLightAPI. \\see \\ref Usd_AutoAppliedAPISchemas ''' ) { uniform token light:materialSyncMode = "materialGlowTintsLight" uniform token light:shaderId = "MeshLight" } class "VolumeLightAPI" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:materialSyncMode", "light:shaderId"] } doc = '''This is the preferred API schema to apply to "Volume" type prims when adding light behaviors to a volume. At its base, this API schema has the built-in behavior of applying LightAPI to the volume and overriding the default materialSyncMode to allow the emission/glow of the bound material to affect the color of the light. But, it additionally serves as a hook for plugins to attach additional properties to "volume lights" through the creation of API schemas which are authored to auto-apply to VolumeLightAPI. \\see \\ref Usd_AutoAppliedAPISchemas ''' ) { uniform token light:materialSyncMode = "materialGlowTintsLight" uniform token light:shaderId = "VolumeLight" } class "LightListAPI" ( doc = '''API schema to support discovery and publishing of lights in a scene. Discovering Lights via Traversal To motivate this API, consider what is required to discover all lights in a scene. We must load all payloads and traverse all prims: \\code 01 // Load everything on the stage so we can find all lights, 02 // including those inside payloads 03 stage->Load(); 04 05 // Traverse all prims, checking if they have an applied UsdLuxLightAPI 06 // (Note: ignoring instancing and a few other things for simplicity) 07 SdfPathVector lights; 08 for (UsdPrim prim: stage->Traverse()) { 09 if (prim.HasAPI()) { 10 lights.push_back(i->GetPath()); 11 } 12 } \\endcode This traversal -- suitably elaborated to handle certain details -- is the first and simplest thing UsdLuxLightListAPI provides. UsdLuxLightListAPI::ComputeLightList() performs this traversal and returns all lights in the scene: \\code 01 UsdLuxLightListAPI listAPI(stage->GetPseudoRoot()); 02 SdfPathVector lights = listAPI.ComputeLightList(); \\endcode Publishing a Cached Light List Consider a USD client that needs to quickly discover lights but wants to defer loading payloads and traversing the entire scene where possible, and is willing to do up-front computation and caching to achieve that. UsdLuxLightListAPI provides a way to cache the computed light list, by publishing the list of lights onto prims in the model hierarchy. Consider a big set that contains lights: \\code 01 def Xform "BigSetWithLights" ( 02 kind = "assembly" 03 payload = @BigSetWithLights.usd@ // Heavy payload 04 ) { 05 // Pre-computed, cached list of lights inside payload 06 rel lightList = [ 07 <./Lights/light_1>, 08 <./Lights/light_2>, 09 ... 10 ] 11 token lightList:cacheBehavior = "consumeAndContinue"; 12 } \\endcode The lightList relationship encodes a set of lights, and the lightList:cacheBehavior property provides fine-grained control over how to use that cache. (See details below.) The cache can be created by first invoking ComputeLightList(ComputeModeIgnoreCache) to pre-compute the list and then storing the result with UsdLuxLightListAPI::StoreLightList(). To enable efficient retrieval of the cache, it should be stored on a model hierarchy prim. Furthermore, note that while you can use a UsdLuxLightListAPI bound to the pseudo-root prim to query the lights (as in the example above) because it will perform a traversal over descendants, you cannot store the cache back to the pseduo-root prim. To consult the cached list, we invoke ComputeLightList(ComputeModeConsultModelHierarchyCache): \\code 01 // Find and load all lights, using lightList cache where available 02 UsdLuxLightListAPI list(stage->GetPseudoRoot()); 03 SdfPathSet lights = list.ComputeLightList( 04 UsdLuxLightListAPI::ComputeModeConsultModelHierarchyCache); 05 stage.LoadAndUnload(lights, SdfPathSet()); \\endcode In this mode, ComputeLightList() will traverse the model hierarchy, accumulating cached light lists. Controlling Cache Behavior The lightList:cacheBehavior property gives additional fine-grained control over cache behavior: - The fallback value, "ignore", indicates that the lightList should be disregarded. This provides a way to invalidate cache entries. Note that unless "ignore" is specified, a lightList with an empty list of targets is considered a cache indicating that no lights are present. - The value "consumeAndContinue" indicates that the cache should be consulted to contribute lights to the scene, and that recursion should continue down the model hierarchy in case additional lights are added as descedants. This is the default value established when StoreLightList() is invoked. This behavior allows the lights within a large model, such as the BigSetWithLights example above, to be published outside the payload, while also allowing referencing and layering to add additional lights over that set. - The value "consumeAndHalt" provides a way to terminate recursive traversal of the scene for light discovery. The cache will be consulted but no descendant prims will be examined. Instancing Where instances are present, UsdLuxLightListAPI::ComputeLightList() will return the instance-unique paths to any lights discovered within those instances. Lights within a UsdGeomPointInstancer will not be returned, however, since they cannot be referred to solely via paths. ''' ) { rel lightList ( doc = "Relationship to lights in the scene." ) token lightList:cacheBehavior ( allowedTokens = ["consumeAndHalt", "consumeAndContinue", "ignore"] doc = """Controls how the lightList should be interpreted. Valid values are: - consumeAndHalt: The lightList should be consulted, and if it exists, treated as a final authoritative statement of any lights that exist at or below this prim, halting recursive discovery of lights. - consumeAndContinue: The lightList should be consulted, but recursive traversal over nameChildren should continue in case additional lights are added by descendants. - ignore: The lightList should be entirely ignored. This provides a simple way to temporarily invalidate an existing cache. This is the fallback behavior. """ ) } class "ListAPI" ( doc = """ \\deprecated Use LightListAPI instead """ ) { rel lightList ( doc = "Relationship to lights in the scene." ) token lightList:cacheBehavior ( allowedTokens = ["consumeAndHalt", "consumeAndContinue", "ignore"] doc = """Controls how the lightList should be interpreted. Valid values are: - consumeAndHalt: The lightList should be consulted, and if it exists, treated as a final authoritative statement of any lights that exist at or below this prim, halting recursive discovery of lights. - consumeAndContinue: The lightList should be consulted, but recursive traversal over nameChildren should continue in case additional lights are added by descendants. - ignore: The lightList should be entirely ignored. This provides a simple way to temporarily invalidate an existing cache. This is the fallback behavior. """ ) } class "ShapingAPI" ( doc = "Controls for shaping a light's emission." ) { float inputs:shaping:cone:angle = 90 ( displayGroup = "Shaping" displayName = "Cone Angle" doc = """Angular limit off the primary axis to restrict the light spread.""" ) float inputs:shaping:cone:softness = 0 ( displayGroup = "Shaping" displayName = "Cone Softness" doc = """Controls the cutoff softness for cone angle. TODO: clarify semantics""" ) float inputs:shaping:focus = 0 ( displayGroup = "Shaping" displayName = "Emission Focus" doc = """A control to shape the spread of light. Higher focus values pull light towards the center and narrow the spread. Implemented as an off-axis cosine power exponent. TODO: clarify semantics""" ) color3f inputs:shaping:focusTint = (0, 0, 0) ( displayGroup = "Shaping" displayName = "Emission Focus Tint" doc = """Off-axis color tint. This tints the emission in the falloff region. The default tint is black. TODO: clarify semantics""" ) float inputs:shaping:ies:angleScale = 0 ( displayGroup = "Shaping" displayName = "Profile Scale" doc = """Rescales the angular distribution of the IES profile. TODO: clarify semantics""" ) asset inputs:shaping:ies:file ( displayGroup = "Shaping" displayName = "IES Profile" doc = """An IES (Illumination Engineering Society) light profile describing the angular distribution of light.""" ) bool inputs:shaping:ies:normalize = 0 ( displayGroup = "Shaping" displayName = "Profile Normalization" doc = """Normalizes the IES profile so that it affects the shaping of the light while preserving the overall energy output.""" ) } class "ShadowAPI" ( doc = """Controls to refine a light's shadow behavior. These are non-physical controls that are valuable for visual lighting work.""" ) { color3f inputs:shadow:color = (0, 0, 0) ( displayGroup = "Shadows" displayName = "Shadow Color" doc = """The color of shadows cast by the light. This is a non-physical control. The default is to cast black shadows.""" ) float inputs:shadow:distance = -1 ( displayGroup = "Shadows" displayName = "Shadow Max Distance" doc = """The maximum distance shadows are cast. The distance is measured as the distance between the point on the surface and the occluder. The default value (-1) indicates no limit. """ ) bool inputs:shadow:enable = 1 ( displayGroup = "Shadows" displayName = "Enable Shadows" doc = "Enables shadows to be cast by this light." ) float inputs:shadow:falloff = -1 ( displayGroup = "Shadows" displayName = "Shadow Falloff" doc = """The size of the shadow falloff zone within the shadow max distance, which can be used to hide the hard cut-off for shadows seen stretching past the max distance. The falloff zone is the area that fades from full shadowing at the beginning of the falloff zone to no shadowing at the max distance from the occluder. The falloff zone distance cannot exceed the shadow max distance. A falloff value equal to or less than zero (with -1 as the default) indicates no falloff. """ ) float inputs:shadow:falloffGamma = 1 ( displayGroup = "Shadows" displayName = "Shadow Falloff Gamma" doc = """A gamma (i.e., exponential) control over shadow strength with linear distance within the falloff zone. This controls the rate of the falloff. This requires the use of shadowDistance and shadowFalloff.""" ) } class LightFilter "LightFilter" ( apiSchemas = ["CollectionAPI:filterLink"] customData = { token[] apiSchemaOverridePropertyNames = ["collection:filterLink:includeRoot"] } doc = """A light filter modifies the effect of a light. Lights refer to filters via relationships so that filters may be shared. Linking Filters can be linked to geometry. Linking controls which geometry a light-filter affects, when considering the light filters attached to a light illuminating the geometry. Linking is specified as a collection (UsdCollectionAPI) which can be accessed via GetFilterLinkCollection(). """ ) { uniform bool collection:filterLink:includeRoot = 1 uniform token lightFilter:shaderId = "" ( displayGroup = "Internal" doc = """Default ID for the light filter's shader. This defines the shader ID for this light filter when a render context specific shader ID is not available. \\see GetShaderId \\see GetShaderIdAttrForRenderContext \\see SdrRegistry::GetShaderNodeByIdentifier \\see SdrRegistry::GetShaderNodeByIdentifierAndType """ ) rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class "BoundableLightBase" ( apiSchemas = ["LightAPI"] doc = """Base class for intrinsic lights that are boundable. The primary purpose of this class is to provide a direct API to the functions provided by LightAPI for concrete derived light types. """ ) { float3[] extent ( doc = """Extent is a three dimensional range measuring the geometric extent of the authored gprim in its own local space (i.e. its own transform not applied), without accounting for any shader-induced displacement. If __any__ extent value has been authored for a given Boundable, then it should be authored at every timeSample at which geometry-affecting properties are authored, to ensure correct evaluation via ComputeExtent(). If __no__ extent value has been authored, then ComputeExtent() will call the Boundable's registered ComputeExtentFunction(), which may be expensive, which is why we strongly encourage proper authoring of extent. \\sa ComputeExtent() \\sa \\ref UsdGeom_Boundable_Extent. An authored extent on a prim which has children is expected to include the extent of all children, as they will be pruned from BBox computation during traversal.""" ) rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class "NonboundableLightBase" ( apiSchemas = ["LightAPI"] doc = """Base class for intrinsic lights that are not boundable. The primary purpose of this class is to provide a direct API to the functions provided by LightAPI for concrete derived light types. """ ) { rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class DistantLight "DistantLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["inputs:intensity", "light:shaderId"] } doc = """Light emitted from a distant source along the -Z axis. Also known as a directional light.""" ) { float inputs:angle = 0.53 ( displayGroup = "Basic" displayName = "Angle Extent" doc = """Angular size of the light in degrees. As an example, the Sun is approximately 0.53 degrees as seen from Earth. Higher values broaden the light and therefore soften shadow edges. """ ) float inputs:intensity = 50000 ( doc = """Scales the emission of the light linearly. The DistantLight has a high default intensity to approximate the Sun.""" ) uniform token light:shaderId = "DistantLight" rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class DiskLight "DiskLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:shaderId"] } doc = """Light emitted from one side of a circular disk. The disk is centered in the XY plane and emits light along the -Z axis.""" ) { float3[] extent ( doc = """Extent is a three dimensional range measuring the geometric extent of the authored gprim in its own local space (i.e. its own transform not applied), without accounting for any shader-induced displacement. If __any__ extent value has been authored for a given Boundable, then it should be authored at every timeSample at which geometry-affecting properties are authored, to ensure correct evaluation via ComputeExtent(). If __no__ extent value has been authored, then ComputeExtent() will call the Boundable's registered ComputeExtentFunction(), which may be expensive, which is why we strongly encourage proper authoring of extent. \\sa ComputeExtent() \\sa \\ref UsdGeom_Boundable_Extent. An authored extent on a prim which has children is expected to include the extent of all children, as they will be pruned from BBox computation during traversal.""" ) float inputs:radius = 0.5 ( displayGroup = "Geometry" displayName = "Radius" doc = "Radius of the disk." ) uniform token light:shaderId = "DiskLight" rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class RectLight "RectLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:shaderId"] } doc = """Light emitted from one side of a rectangle. The rectangle is centered in the XY plane and emits light along the -Z axis. The rectangle is 1 unit in length in the X and Y axis. In the default position, a texture file's min coordinates should be at (+X, +Y) and max coordinates at (-X, -Y).""" ) { float3[] extent ( doc = """Extent is a three dimensional range measuring the geometric extent of the authored gprim in its own local space (i.e. its own transform not applied), without accounting for any shader-induced displacement. If __any__ extent value has been authored for a given Boundable, then it should be authored at every timeSample at which geometry-affecting properties are authored, to ensure correct evaluation via ComputeExtent(). If __no__ extent value has been authored, then ComputeExtent() will call the Boundable's registered ComputeExtentFunction(), which may be expensive, which is why we strongly encourage proper authoring of extent. \\sa ComputeExtent() \\sa \\ref UsdGeom_Boundable_Extent. An authored extent on a prim which has children is expected to include the extent of all children, as they will be pruned from BBox computation during traversal.""" ) float inputs:height = 1 ( displayGroup = "Geometry" displayName = "Height" doc = "Height of the rectangle, in the local Y axis." ) asset inputs:texture:file ( displayGroup = "Basic" displayName = "Color Map" doc = "A color texture to use on the rectangle." ) float inputs:width = 1 ( displayGroup = "Geometry" displayName = "Width" doc = "Width of the rectangle, in the local X axis." ) uniform token light:shaderId = "RectLight" rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class SphereLight "SphereLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:shaderId"] } doc = "Light emitted outward from a sphere." ) { float3[] extent ( doc = """Extent is a three dimensional range measuring the geometric extent of the authored gprim in its own local space (i.e. its own transform not applied), without accounting for any shader-induced displacement. If __any__ extent value has been authored for a given Boundable, then it should be authored at every timeSample at which geometry-affecting properties are authored, to ensure correct evaluation via ComputeExtent(). If __no__ extent value has been authored, then ComputeExtent() will call the Boundable's registered ComputeExtentFunction(), which may be expensive, which is why we strongly encourage proper authoring of extent. \\sa ComputeExtent() \\sa \\ref UsdGeom_Boundable_Extent. An authored extent on a prim which has children is expected to include the extent of all children, as they will be pruned from BBox computation during traversal.""" ) float inputs:radius = 0.5 ( displayGroup = "Geometry" displayName = "Radius" doc = "Radius of the sphere." ) uniform token light:shaderId = "SphereLight" rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) bool treatAsPoint = 0 ( displayGroup = "Advanced" displayName = "Treat As Point" doc = """A hint that this light can be treated as a 'point' light (effectively, a zero-radius sphere) by renderers that benefit from non-area lighting. Renderers that only support area lights can disregard this.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class CylinderLight "CylinderLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:shaderId"] } doc = """Light emitted outward from a cylinder. The cylinder is centered at the origin and has its major axis on the X axis. The cylinder does not emit light from the flat end-caps. """ ) { float3[] extent ( doc = """Extent is a three dimensional range measuring the geometric extent of the authored gprim in its own local space (i.e. its own transform not applied), without accounting for any shader-induced displacement. If __any__ extent value has been authored for a given Boundable, then it should be authored at every timeSample at which geometry-affecting properties are authored, to ensure correct evaluation via ComputeExtent(). If __no__ extent value has been authored, then ComputeExtent() will call the Boundable's registered ComputeExtentFunction(), which may be expensive, which is why we strongly encourage proper authoring of extent. \\sa ComputeExtent() \\sa \\ref UsdGeom_Boundable_Extent. An authored extent on a prim which has children is expected to include the extent of all children, as they will be pruned from BBox computation during traversal.""" ) float inputs:length = 1 ( displayGroup = "Geometry" displayName = "Length" doc = "Length of the cylinder, in the local X axis." ) float inputs:radius = 0.5 ( displayGroup = "Geometry" displayName = "Radius" doc = "Radius of the cylinder." ) uniform token light:shaderId = "CylinderLight" rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) bool treatAsLine = 0 ( displayGroup = "Advanced" displayName = "Treat As Line" doc = """A hint that this light can be treated as a 'line' light (effectively, a zero-radius cylinder) by renderers that benefit from non-area lighting. Renderers that only support area lights can disregard this.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class GeometryLight "GeometryLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:shaderId"] } doc = """\\deprecated Light emitted outward from a geometric prim (UsdGeomGprim), which is typically a mesh.""" ) { rel geometry ( doc = "Relationship to the geometry to use as the light source." ) uniform token light:shaderId = "GeometryLight" rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class DomeLight "DomeLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:shaderId"] } doc = """Light emitted inward from a distant external environment, such as a sky or IBL light probe. The orientation of a dome light with a latlong texture is expected to match the OpenEXR specification for latlong environment maps. From the OpenEXR documentation: ------------------------------------------------------------------------- Latitude-Longitude Map: The environment is projected onto the image using polar coordinates (latitude and longitude). A pixel's x coordinate corresponds to its longitude, and the y coordinate corresponds to its latitude. Pixel (dataWindow.min.x, dataWindow.min.y) has latitude +pi/2 and longitude +pi; pixel (dataWindow.max.x, dataWindow.max.y) has latitude -pi/2 and longitude -pi. In 3D space, latitudes -pi/2 and +pi/2 correspond to the negative and positive y direction. Latitude 0, longitude 0 points into positive z direction; and latitude 0, longitude pi/2 points into positive x direction. The size of the data window should be 2*N by N pixels (width by height), where N can be any integer greater than 0. ------------------------------------------------------------------------- """ ) { float guideRadius = 100000 ( displayGroup = "Guides" displayName = "Radius" doc = "The radius of guide geometry to use to visualize the dome light. The default is 1 km for scenes whose metersPerUnit is the USD default of 0.01 (i.e., 1 world unit is 1 cm)." ) asset inputs:texture:file ( displayGroup = "Basic" displayName = "Color Map" doc = """A color texture to use on the dome, such as an HDR (high dynamic range) texture intended for IBL (image based lighting).""" ) token inputs:texture:format = "automatic" ( allowedTokens = ["automatic", "latlong", "mirroredBall", "angular", "cubeMapVerticalCross"] displayGroup = "Basic" displayName = "Color Map Format" doc = """Specifies the parameterization of the color map file. Valid values are: - automatic: Tries to determine the layout from the file itself. For example, Renderman texture files embed an explicit parameterization. - latlong: Latitude as X, longitude as Y. - mirroredBall: An image of the environment reflected in a sphere, using an implicitly orthogonal projection. - angular: Similar to mirroredBall but the radial dimension is mapped linearly to the angle, providing better sampling at the edges. - cubeMapVerticalCross: A cube map with faces laid out as a vertical cross. """ ) uniform token light:shaderId = "DomeLight" rel portals ( doc = "Optional portals to guide light sampling." ) rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class PortalLight "PortalLight" ( apiSchemas = ["LightAPI"] customData = { token[] apiSchemaOverridePropertyNames = ["light:shaderId"] } doc = """A rectangular portal in the local XY plane that guides sampling of a dome light. Transmits light in the -Z direction. The rectangle is 1 unit in length.""" ) { float3[] extent = [(-0.5, -0.5, 0), (0.5, 0.5, 0)] ( doc = """Boundary extent of the unit rectangle in the XY plane that defines the portal.""" ) uniform token light:shaderId = "PortalLight" rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class PluginLight "PluginLight" ( apiSchemas = ["NodeDefAPI", "LightAPI"] doc = """Light that provides properties that allow it to identify an external SdrShadingNode definition, through UsdShadeNodeDefAPI, that can be provided to render delegates without the need to provide a schema definition for the light's type. \\see \\ref usdLux_PluginSchemas """ ) { rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) } class PluginLightFilter "PluginLightFilter" ( apiSchemas = ["NodeDefAPI", "CollectionAPI:filterLink"] customData = { token[] apiSchemaOverridePropertyNames = ["collection:filterLink:includeRoot"] } doc = """Light filter that provides properties that allow it to identify an external SdrShadingNode definition, through UsdShadeNodeDefAPI, that can be provided to render delegates without the need to provide a schema definition for the light filter's type. \\see \\ref usdLux_PluginSchemas """ ) { uniform bool collection:filterLink:includeRoot = 1 uniform token lightFilter:shaderId = "" ( displayGroup = "Internal" doc = """Default ID for the light filter's shader. This defines the shader ID for this light filter when a render context specific shader ID is not available. \\see GetShaderId \\see GetShaderIdAttrForRenderContext \\see SdrRegistry::GetShaderNodeByIdentifier \\see SdrRegistry::GetShaderNodeByIdentifierAndType """ ) rel proxyPrim ( doc = '''The proxyPrim relationship allows us to link a prim whose purpose is "render" to its (single target) purpose="proxy" prim. This is entirely optional, but can be useful in several scenarios: - In a pipeline that does pruning (for complexity management) by deactivating prims composed from asset references, when we deactivate a purpose="render" prim, we will be able to discover and additionally deactivate its associated purpose="proxy" prim, so that preview renders reflect the pruning accurately. - DCC importers may be able to make more aggressive optimizations for interactive processing and display if they can discover the proxy for a given render prim. - With a little more work, a Hydra-based application will be able to map a picked proxy prim back to its render geometry for selection. \\note It is only valid to author the proxyPrim relationship on prims whose purpose is "render".''' ) uniform token purpose = "default" ( allowedTokens = ["default", "render", "proxy", "guide"] doc = """Purpose is a classification of geometry into categories that can each be independently included or excluded from traversals of prims on a stage, such as rendering or bounding-box computation traversals. See for more detail about how purpose is computed and used.""" ) token visibility = "inherited" ( allowedTokens = ["inherited", "invisible"] doc = '''Visibility is meant to be the simplest form of "pruning" visibility that is supported by most DCC apps. Visibility is animatable, allowing a sub-tree of geometry to be present for some segment of a shot, and absent from others; unlike the action of deactivating geometry prims, invisible geometry is still available for inspection, for positioning, for defining volumes, etc.''' ) uniform token[] xformOpOrder ( doc = """Encodes the sequence of transformation operations in the order in which they should be pushed onto a transform stack while visiting a UsdStage's prims in a graph traversal that will effect the desired positioning for this prim and its descendant prims. You should rarely, if ever, need to manipulate this attribute directly. It is managed by the AddXformOp(), SetResetXformStack(), and SetXformOpOrder(), and consulted by GetOrderedXformOps() and GetLocalTransformation().""" ) }